NSF Postdoctoral Fellowship in Biology FY 2020: Diet and the microbiome as drivers of host tolerance and resistance to parasites

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2020, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment and Phenotypes. The fellowship supports research and training of the fellow that will contribute to the area of Rules of Life in innovative ways. This research investigates how diet and the gut microbiome (microbes that live and play essential roles in the digestive track of animals) influences host defenses against parasites.

Many factors can influence the diet of wildlife, including shifts in nutritional resources due to seasonality, habitat alteration, and supplemental feeding by humans. Shifts in dietary nutrients, such as proteins and fats, can affect the immune system and influence an animal’s ability to defend against parasites. The effects of diet on immunity could be mediated by changes in the composition and function of the gut microbiome.

The goal of this research is to determine how dietary nutrients and the gut microbiome affect interactions between box-nesting eastern bluebirds (Sialia sialis) and the parasitic nest fly (Protocalliphora sialia). This research will shed light on how nutritional resources influence host immunity and will yield predictive insight into how organisms and their parasites will respond to environmental shifts in diet.

The project will also promote the education of high school and undergraduate students through training in research and professional development.

Box-nesting birds offer an ideal system to explore relationships between nutrition, immunity, gut microflora, and parasitism as nests are commonly parasitized and parasite load can be non-invasively quantified through the collection of nests after offspring fledge. This system also offers strong experimental capabilities in a field setting, where nestling diet can be manipulated by feeding nestlings and dosing offspring with an oral antibiotic can experimentally disrupt nestling gut microflora.

Using a factorial design, diet macronutrient content and the gut microbiome will be manipulated in nestling bluebirds and then nestling immunity, gut microflora, and parasite abundance will be characterized. Additionally, the research will determine whether gut symbionts produce immune-modulatory metabolites that shape host gene expression and host-parasite interactions.

The project will facilitate the fellow’s training and growth in transcriptomics and metabolomics. The proposed work will also include broader impacts through the direct involvement of high school and undergraduate mentees in data collection, public educational programs, and the development of K-12 activities related to the research.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.